4.0 ohv to 4.0 sohc swap
#1
4.0 ohv to 4.0 sohc swap
Hi I have a 93 Ford ranger with a 4.0 ohv in it and a 5 speed with 4x4. We had to put a new motor in awhile because the heads cracked and the new one isn't much better. My buddy gave me a 4.0 sohc from a 98 explorer with a automatic that was 4x4 and I was just wondering what all I'd have to do to put the 98 motor into my 93 truck with the manaul trans. Mostly what computer do I need? And if I have to get one other than the 93 does it matter if it comes from a automatic or manual and what all will plug up.
#2
RF Veteran
iTrader: (1)
The 4.0l OHV and 4.0l SOHC have the same bell housing bolt pattern, SOHC has extra bolt hole but isn't "required".
They also both use the same engine mounts.
BUT(big but), your '93 uses EEC-IV computer(OBDI) and '95 and up Computers are EEC-V(OBDII) and require more sensors and wiring to work.
So you would need computer and wiring harness from '97(1st year) or up explorer or 2001 and up Ranger with 4.0l SOHC, and it must be for Manual Trans or you will also need to swap in the automatic.
You will need to add O2 sensors on the rear exhaust for the cat converters as well.
Also the early 4.0l SOHC engines(pre-2005) need to have new timing chain kits installed.
IMO it isn't a good swap, but up to you really.
Not sure why you would be having issues with the 4.0l OHV, it was one of the most reliable engines used in Rangers, 1990-2000, yes if overheated the heads would crack, but only if overheated, weak spot between valve seats.
Other than that they were bullet proof.
I am just passing 350k on original 4.0l in my '94, yes I did replace the heads but it was my own fault, I tried to "make it home" after I lost a hose and coolant, $400 goof, lol.
They also both use the same engine mounts.
BUT(big but), your '93 uses EEC-IV computer(OBDI) and '95 and up Computers are EEC-V(OBDII) and require more sensors and wiring to work.
So you would need computer and wiring harness from '97(1st year) or up explorer or 2001 and up Ranger with 4.0l SOHC, and it must be for Manual Trans or you will also need to swap in the automatic.
You will need to add O2 sensors on the rear exhaust for the cat converters as well.
Also the early 4.0l SOHC engines(pre-2005) need to have new timing chain kits installed.
IMO it isn't a good swap, but up to you really.
Not sure why you would be having issues with the 4.0l OHV, it was one of the most reliable engines used in Rangers, 1990-2000, yes if overheated the heads would crack, but only if overheated, weak spot between valve seats.
Other than that they were bullet proof.
I am just passing 350k on original 4.0l in my '94, yes I did replace the heads but it was my own fault, I tried to "make it home" after I lost a hose and coolant, $400 goof, lol.
#3
[QUOTE=RonD;2097016]The 4.0l OHV and 4.0l SOHC have the same bell housing bolt pattern, SOHC has extra bolt hole but isn't "required".
They also both use the same engine mounts.
BUT(big but), your '93 uses EEC-IV computer(OBDI) and '95 and up Computers are EEC-V(OBDII) and require more sensors and wiring to work.
So you would need computer and wiring harness from '97(1st year) or up explorer or 2001 and up Ranger with 4.0l SOHC, and it must be for Manual Trans or you will also need to swap in the automatic.
You will need to add O2 sensors on the rear exhaust for the cat converters as well.
Also the early 4.0l SOHC engines(pre-2005) need to have new timing chain kits installed.
IMO it isn't a good swap, but up to you really.
Not sure why you would be having issues with the 4.0l OHV, it was one of the most reliable engines used in Rangers, 1990-2000, yes if overheated the heads would crack, but only if overheated, weak spot between valve seats.
Other than that they were bullet proof.
I am just passing 350k on original 4.0l in my '94, yes I did replace the heads but it was my own fault, I tried to "make it home" after I lost a hose and coolant, $400 goof, lol.[/QUOT
I have the wiring harness on the motor from the automatic or do I need a wiring harness from a 5 speed and I can find a 5 speed computer. Will that wiring harness plug into the one under the dash of my truck or not?
They also both use the same engine mounts.
BUT(big but), your '93 uses EEC-IV computer(OBDI) and '95 and up Computers are EEC-V(OBDII) and require more sensors and wiring to work.
So you would need computer and wiring harness from '97(1st year) or up explorer or 2001 and up Ranger with 4.0l SOHC, and it must be for Manual Trans or you will also need to swap in the automatic.
You will need to add O2 sensors on the rear exhaust for the cat converters as well.
Also the early 4.0l SOHC engines(pre-2005) need to have new timing chain kits installed.
IMO it isn't a good swap, but up to you really.
Not sure why you would be having issues with the 4.0l OHV, it was one of the most reliable engines used in Rangers, 1990-2000, yes if overheated the heads would crack, but only if overheated, weak spot between valve seats.
Other than that they were bullet proof.
I am just passing 350k on original 4.0l in my '94, yes I did replace the heads but it was my own fault, I tried to "make it home" after I lost a hose and coolant, $400 goof, lol.[/QUOT
I have the wiring harness on the motor from the automatic or do I need a wiring harness from a 5 speed and I can find a 5 speed computer. Will that wiring harness plug into the one under the dash of my truck or not?
#4
RF Veteran
iTrader: (1)
Finding a manual 4.0l SOHC without PATS will be hard, only source is Explorer '97/'98 and they were 95% automatics, if not more.
PATS is Ford's Passive anti-theft system, it is inside the computer so no way to by-pass it, if you use one of these then you need to change ignition key to work with the PATS keys that MUST come with the computer, if you don't get the PATS keys with the computer then you will have to have a mobile locksmith come out that has the Ford software to add new PATS keys, it can only be done with computer in the vehicle.
You can send out an automatic computer to a programmer and they can change it to Manual, also remove PATS, I would budget $400 for that but never done it so not sure
1993 has speedometer cable and analog gauges so no computer hook up is needed.
There will be some basic power wiring changes needed, 1993 and 1998 wiring will be different.
PATS is Ford's Passive anti-theft system, it is inside the computer so no way to by-pass it, if you use one of these then you need to change ignition key to work with the PATS keys that MUST come with the computer, if you don't get the PATS keys with the computer then you will have to have a mobile locksmith come out that has the Ford software to add new PATS keys, it can only be done with computer in the vehicle.
You can send out an automatic computer to a programmer and they can change it to Manual, also remove PATS, I would budget $400 for that but never done it so not sure
1993 has speedometer cable and analog gauges so no computer hook up is needed.
There will be some basic power wiring changes needed, 1993 and 1998 wiring will be different.
#5
#6
Bigger injectors, how big, will they alone really help. Or, would this require a larger TB ???
#7
RF Veteran
iTrader: (1)
No, larger injectors won't help on their own, with or without larger TB.
There are 2 ways to give a vehicle more power
1. Power to weight ratio, reduce the weight of the vehicle
2. increase the amount of air the engine can use on each stroke, i.e. turbo/super chargers or Stroker kit, example: changes 4.0l to 4.3l
When you increase the amount of air you can add more fuel so get more power, just adding more fuel and you will lose power.
Increasing compression is also an option but then you can't run regular(87 octane) fuel.
Unless you use a Knock detector like they had to do on the 4.0l SOHC, so it's higher horse power rating is based on running Premium(91+ octane) fuel.
Larger TB doesn't add more air unless factory TB was restricting air, which is doesn't.
And all fuel injected engines now come with cold air intakes and air filters that are rated 200% of engine capacity, i.e. a 4 liter engine(4.0l) uses 4 liters of air every 2 RPMs, air intake and filter can pass 8 liters of air every 2 RPMs, so 200% capacity
There are 2 ways to give a vehicle more power
1. Power to weight ratio, reduce the weight of the vehicle
2. increase the amount of air the engine can use on each stroke, i.e. turbo/super chargers or Stroker kit, example: changes 4.0l to 4.3l
When you increase the amount of air you can add more fuel so get more power, just adding more fuel and you will lose power.
Increasing compression is also an option but then you can't run regular(87 octane) fuel.
Unless you use a Knock detector like they had to do on the 4.0l SOHC, so it's higher horse power rating is based on running Premium(91+ octane) fuel.
Larger TB doesn't add more air unless factory TB was restricting air, which is doesn't.
And all fuel injected engines now come with cold air intakes and air filters that are rated 200% of engine capacity, i.e. a 4 liter engine(4.0l) uses 4 liters of air every 2 RPMs, air intake and filter can pass 8 liters of air every 2 RPMs, so 200% capacity
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